I was able to add a file as-link to an project, as you can see in the image:
see the difference in the icon for files added as-link and files added as"normal"
but now don't remember how to add a file as link, or if this was because some add-in.
I've vs2010 installed in both desktop and laptop, the same of a few coworkers, and I like to have several general file (used as links) in different folders as the project folders.
anyway don't sure of as-link or normal are important in an project.
the only difference I've noted is that link files can't be edited when in debug.
basically I'm thinking in add as-link the files that are shared/used in several projects, as general modules or classes that have functions or subs intended to be as shared.
so the question mainly is
¿ how to add a file as-link ?
Select the Add Existing Item option, either by right-clicking the project in the Solution Explorer or from the Project menu. Select a file and then click the drop-down arrow on the Add button. You'll find the option you want there.